const path = require('path');

const filepath = 'c:/a/b/c/d.html';

// console.log( path.basename(filepath) );

// console.log( path.dirname(filepath) );

// console.log( __dirname);

// console.log(__filename);

// console.log(path.join(__dirname,'./data/user.txt'));

// console.log(path.resolve('./data/user.txt'));

console.log(path.extname('./data/user.txt'));